Eisai announced that an investigational study of its antiobesity drug lorcaserin hydrochloride (US brand name: BELVIQ;“lorcaserin”) when coadministered with phentermine hydrochloride (“phentermine”) jointly conducted by its US subsidiary Eisai and Arena Pharmaceuticals, met its primary safety objective.

The results of the study demonstrate that the short-term combination of lorcaserin plus phentermine does not appear to be associated with an exacerbation in the proportion of pre-specified adverse events compared to therapy with lorcaserin alone.

The detailed results of the trial are to be presented at ObesityWeek2014 which is the Annual Meeting of The Obesity Society and the American Society for Metabolic and Bariatric Surgery held in Boston from November 2 to 7, 2014.

The coadministration of lorcaserin and phentermine for weight management is investigational. The efficacy and safety of coadministration of lorcaserin and other weight loss products such as phentermine have not been established. The study was a randomised, double-blind study of 12-weeks duration in 238 overweight and obese adult patients designed to evaluate whether treatment with lorcaserin plus phentermine is associated with exacerbation of potential serotonergic adverse events compared to lorcaserin alone.

Patients were randomised 1:1:1 to one of three treatment arms consisting of either lorcaserin alone (10 mg twice daily), lorcaserin (10 mg twice daily) with phentermine (15 mg once daily) orlorcaserin (10 mg twice daily) with phentermine (15 mg twice daily). In addition, patients received standardised weight-loss counselling throughout the trial.

The objective of the trial was to assess the proportion of subjects reporting at least one of nine common potential serotonergic adverse events (headache, dizziness, nausea, fatigue, dry mouth, diarrhoea,vomiting, insomnia, and/or anxiety) from baseline to the end of treatment.

The most common adverse events that occurred during the trial were headache, fatigue, insomnia, dizziness, dry mouth an constipation.

Through lorcaserin, Eisai is committed to making further contributions to address unmet medical needs that exist in the clinical management of obesity.